Japan uses 100V AC (60Hz) USA uses 120V AC (60Hz)
but that only applies to devices that injest AC power from the wall outlets. So the arcade cabinet itself, NOT the game PCB.
most arcade cabinets can support between 100V and 120V AC and don't require a step down converter. I've got 8 Japanese market machines and none of them have nor require step-down converters.
The reason the Japanese market PS2 needs one (though I'm not sure that it actually does) is that the power-supply is integrated into the console; that's not the case for most arcade PCBs including the System 246 PCBs.
